The present invention relates to a surgical cutting instrument. More particularly, it relates to a surgical cutting instrument adapted to facilitate cutting window rotation.
Surgical cutting instruments in which an elongate inner member is rotated within an elongate outer tubular member have become well accepted in surgical procedures where access to the surgical site is gained via a narrow portal or passage. Typically, the outer tubular member includes a distal end with an opening defining a cutting port or window, and the inner member includes a distal end forming a cutting tip for cutting bodily tissue at the window. Proximal ends of the inner and outer members are commonly secured to hubs that, in turn, are attached to a powered handpiece for rotating and/or oscillating the inner member relative to the outer tubular member. The cutting tip of the inner member can have various configurations specific to the surgical procedure in question (e.g., cutting, resecting, abrading, shaving, etc.), with the cutting window being suitably configured to cooperate with the particular configuration of the cutting tip. Often, the inner member is tubular so that the loose tissue resulting from a cutting, resecting, or abrading procedure can be aspirated through the hollow lumen of the inner member.
Use of the above-described surgical cutting instruments generally entails delivering the cutting window/cutting tip to the target site and positioning the cutting window such that the cutting tip is “exposed” to the desired tissue. To this end, with conventional surgical cutting instruments, while the inner member, and thus the cutting tip, is rotatable relative to the handpiece, the outer tubular member, and thus the cutting window, is not. That is to say, a rotational or spatial position of the cutting window relative to the handpiece is fixed with most available surgical cutting instruments. As a result, in order to spatially position the cutting window so as to expose the cutting tip to desired tissue, the surgeon must physically move or rotate the handpiece. In many instances, this requires the surgeon to contort his or her hand(s) to an otherwise uncomfortable position. Further, many surgical procedures require that tissue at different spatial locations at a particular target site be acted upon by the cutting tip. Thus, while upon initial placement at the target site the cutting window may be properly oriented for a first portion of the procedure, tissue at a different spatial location will also require removal, in turn requiring that the spatial position of the cutting window be altered or rotated. Once again, with conventional surgical cutting instruments, this procedural specification requires the surgeon to physically change the orientation of the handpiece, thus taxing the surgeon's hand(s) and/or requiring the surgeon to temporarily halt the procedure and move to a different physical position relative to the patient.
Where the surgical cutting instrument is used in conjunction with an image guided surgery (IGS) system, additional concerns may arise. In particular, IGS generally entails registering the cutting window/cutting tip once deployed to the target site. Where the cutting window spatial orientation must be changed during the procedure, surgeons will commonly remove the instrument from the patient to more easily re-orientate the handpiece and thus the cutting window. When this is done, and following reinsertion of the cutting instrument, the cutting window/cutting tip must be re-registered relative to the IGS system, thereby extending the surgical procedure time.
The need to remove the surgical cutting instrument during a surgical procedure to effectuate a change in the cutting window spatial orientation is routinely encountered where the surgical cutting instrument includes one or more bends along a longitudinal length thereof. As a point of reference, some surgical cutting instruments, and in particular the outer tubular member thereof, are straight or linear along their longitudinal length. Others are curved in accordance with a specific procedure to facilitate positioning of the cutting tip against expected target site tissue. With the curved or bent configuration, the cutting window will move in an irregular fashion with rotation of the handpiece, effectively rotating about the bend or longitudinal point of curvature. Under these circumstances, then, it is virtually impossible for the surgeon to accurately alter the cutting window position without first removing the surgical cutting instrument from the patient.
Surgical cutting instruments continue to be extremely useful. However, the inability to readily and conveniently change a rotational orientation of the cutting window at the target site has not been fully addressed. Therefore, a need exists for a surgical cutting instrument capable of effectuating rotation of the cutting window relative to the handpiece operation with minimal impact on user visibility.